HTML Code

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>touchcancel basic</title>
  <style>
    #pad {
      width: 260px; height: 120px; border: 2px solid #333;
      display: flex; align-items: center; justify-content: center;
      touch-action: none; user-select: none; background: #f5f5f5;
    }
  </style>
</head>
<body>
  <div id="pad">Touch here, then cancel</div>
  <p><button type="button" id="sim">Simulate cancel log</button></p>
  <pre id="out">waiting…</pre>
  <script>
    var pad = document.getElementById("pad");
    var out = document.getElementById("out");
    function logCancel(n) {
      out.textContent = "touchcancel · changed=" + n;
    }
    pad.addEventListener("touchcancel", function (event) {
      logCancel(event.changedTouches.length);
    });
    document.getElementById("sim").onclick = function () {
      logCancel(1);
    };
  </script>
</body>
</html>

Lines: 0 | Characters: 0

Live Preview Auto-refresh on Run

Element touchcancel — log cancel (Try It)